Plug-in And Play

Logic Tips & Techniques

Logic X has a new category of plug-ins for software instruments called 'MIDI plug-ins', which are really rather exciting. I'll save the flagship Arpeggiator for its own workshop in coming months, but this column will examine some of the other incredibly useful MIDI effects for building tracks. These are Chord Trigger, Modulator, Transposer, Velocity Processor, Scriptor and Note Repeater. Many of these effects existed previously in Logic's Environment or in the MIDI editors, but they were never this elegant and certainly not as easy to use.

The MIDI effect slot is directly above the software instrument insert in Logic's channel strip. Click the slot and choose a specific plug-in from the pop-up menu. Once a MIDI effect is selected, click the green horizontal line beneath to add another plug-in from the same pop-up menu. To remove a MIDI plug-in, choose No Plug-in from this menu. To bypass, click the arrows on the left side of the plug-in label or use the traditional Option-click method. You'll notice MIDI plug-ins are green, rather than blue, which makes them easy to differentiate from audio plug-ins on the channel strip.Adding a MIDI plug-in to a software instrument channel strip.

This next move could make you a far more productive Logic Pro X user. Say you choose a MIDI plug-in preset or design your own chain of MIDI plug-in settings, then decide you want to hear it with a different patch. At the bottom left of the Library, click the settings icon and enable Patch Merging, then deselect MIDI Effects (see screen later in this workshop) to keep the MIDI plug-in setting when you switch to another patch.Use Patch Merging to try out the same MIDI plug-in settings with different patches.

As the name suggests, the Chord Trigger plug-in triggers a chord from a single MIDI note. The plug-in's on-screen keyboards show incoming and outgoing MIDI notes respectively. The top keyboard, labelled Input, displays the key you play, while the keyboard below, labelled Output, shows the chord being played back.

Here are some easy steps to making a Chord Trigger assignment:

1. Insert Chord Trigger on a strings patch such as Epic Synth Strings.

2. Click the Learn button. It flashes in red and the Input Keyboard turns blue.

3. Click a trigger key, such as C2, on the Input Keyboard. A red dot will appear on the chosen key.

4. Click on the lower keyboard to assign the notes to be triggered. Try an F minor 7th chord (F, A flat, C, E flat).

5. Hit Learn again to complete the process.

6. Play any key on your controller keyboard, and the chord type you assigned will be triggered.

7. Optional: Drag the left and right side of the bar labelled Trigger Keys above the upper keyboard to restrict the note range that will be processed.

Assign a small trigger range in order to solo over with the rest of your keyboard. Use the Clear button to erase a Trigger Key and corresponding chord to make a different assignment.

The Single and Multi buttons on the upper left are useful. Single is the mode we've used so far, and assigns a single memorised chord that gets transposed — so the same chord type, such as a minor triad, is triggered by every key.

Multi chord mode lets you assign individual chords to different keys so that different types of chords can be triggered by playing different notes. For instance, you could assign a C Maj 7th chord to C2 and a C# min 7th to D2. Try transposing up an octave (12 semitones) on the parameter labelled Chord Transpose located between the two keyboards. Now play C2 and D2 on your controller keyboard rhythmically against a beat. Pressing just two keys creates a musical chord progression.Introducing some of the new creative Logic Pro X plug-ins: Chord Trigger, Modulator, Transposer, Velocity Processor, Scriptor and Note Repeater.

The immediate sound morphing achieved with Modulator is a dream come true for any Logic user who's into sound design. To adjust your eye to the plug-in design, notice first that it's divided into two sections: the LFO on the left and the Envelope Generator on the right, both individually enabled using large buttons at the top left of each module. These modulation sources can be routed to different destinations from the pop-up menu to create distinct, pulsing, timbral changes. Route to pitch and the result is vibrato, whereas if you route to volume you get a tremolo effect instead.

Load Modulator on a pad texture like the Cosmic Dust factory patch and explore these Modulator parameters, first with a default destination of Mod Wheel.

LFO section (left)

1. Experiment with the waveform shape. All of the waveshapes — triangle, sine, square and random square — are very musical with this patch.

2. Use the Symmetry slider beneath the waveform shape to adjust the LFO cycle for subtle timbral changes. The LFO produces a continuous stream of controller events and creates a stepped controller signal when its label is Steps per LFO Cycle. With a square or random waveform, the slider is renamed Smoothing because it smooths out the steep slope on these waveforms. Press Play to hear Modulator pulsing in time with anything rhythmic in your track.

3. The Rate Knob changes the LFO cycle speed. Enable the adjacent sync button to synchronise to the song tempo and display beat values instead of Hertz.

4. The Oscilloscope at the bottom displays the shape of the LFO control signal being adjusted by Shape and Rate. This is an important visual aid for appreciating what the LFO and Envelope knob adjustments do — as well as providing pretty trippy visual feedback while you're working!

7. The ENV to LFO Rate and ENV to LFO Amp knobs adjust LFO modulation. Listen to the difference while turning these knobs from hard left to right.

Changes in LFO rates create many familiar effects in modern electronic dance and film music. Low rates can work well for modulating low-pass filter cutoffs, while higher rates, combined with higher settings on the Amp control, will produce more intense 'wobble' effects.

Transposer changes the pitch of incoming MIDI notes in real time to a selected musical scale. Try it first on a simple piano patch. Use the Transpose slider at the top to shift incoming MIDI notes up or down, or type in a value. Choose the root note for the scale on the left, then the scale from the pop-up menu on the right. Try a dramatic choice like the South-East Asian scale to hear how the notes you play conform to the selected scale and key.

The pop-up Scale menu lists the extensive choice of scales available. Create your own custom scale with the on-screen keyboard by selecting User Scale, and simply switch notes on and off. For example, you could select all the black keys. The possibilities for evolving music melodically with this MIDI plug-in alone are limited only by your own imagination.

Next, try adding the Velocity Processor to the same instrument, as described above. This plug-in behaves like an audio compressor or limiter, allowing you to control velocity on input with the Value slider. Set the slider to a low value and no matter how loud or hard you play, the results will be a consistent volume.

Then there's Scriptor, which allows you to write your own scripts to process or generate MIDI data in real time, letting you design your own MIDI plug-ins using Javascript. Like any other plug-in, Scriptor has settings you can load. A number of extremely cool Scriptor processors are included as presets for chord strumming, generating harp glissandi and for algorithmic composition. One of my favorites is Harpeggiator, which is stunning on a patch like Scatter Pad from the Plucked Synth category. Try adding Transposer beneath and select the Japanese scale for a really dreamy result.

When you load some of these example settings, they will reconfigure the faders in the controls view to give you real-time control over the features written in Javascript. Examine how the factory presets scripts are constructed by clicking Open Script in Editor.

Finally, we have Note Repeater. Think of it like an audio delay generating repeated notes with a few perfect controls. It works well on an edgy or smooth synth patch such as the Lyrical Synth. With Delay Sync enabled, Note Repeater syncs with Logic's tempo and displays in bars/beat values instead of milliseconds. Set the delay time to 1/4 notes with the Delay slider, then experiment with the number of repeats using the Repeats knob beneath.

The Display area shows the MIDI note as a bright bar followed by the processed, repeated notes. Watch the display update as you adjust the number of repeats. Try increasing the number of repeats to at least 40. Play with the Velocity Ramp to adjust whether repeated notes get louder or softer. The Transpose control can make things a little crazy, altering the pitch of the repeated notes, but may be useful for scoring video games or animation.

The new MIDI plug-ins are great, and will certainly provide that instant pick-me-up to the creative process in Logic. The introduction of these processors as real-time plug-ins has been done so well, we can almost forgive Apple for making us wait so long for them! .